Can anyone who has got one of these or had one let me know about the following areas;
fuel consumption ie where do they stop being more economical and become the same as a 2 stroke on oil and fuel?
Reliability?
servicing costs?
parts backup?
The reason is that after 2 years I have decided to buy a bigger boat and have been offered one of these 300hp yammys on the deal. At present I run the 150 optimax but cannot afford 2 and they don't do a 300!!
All advice appreciated.The merc was 100 % reliable
Mike

I have 2 X 300 HPDI on my boat and as long as the engine is running it`s great but i been having some probs with overheating and the lower pistons craculates.
We been having same problem with a singel 300 also.
I don`t really think that the engine is giving 300hp either, we tested a 250VMAX HPDI (gives 274hp) on almost same boat and the VMAX was 4 knots faster and we tested different props but it was always a different between the engines.
The consumption on my boat on 5,500-5,600 refs is around 225 liter per hour wich means 112,5 liter plus a little bit more on a singel engine.
I don`t really think that service costs in Sweden are the same as in UK, here it`s around 215 €uro per engine ex VAT.
When it comes to parts Yamaha is great, we get the stuff from Belgium were all the parts distributes out in Europe in a couple of days if there is something serious on the engine, ususally they have small parts in stock at Yamaha Center here.
Personally i would go for a Yamaha 250 VMAX HPDI for singel setup not for twin engines because there is no counter rotating VMAX engine.

Hi Mike
I have run HPDI's for five years now and I would never have them again. Our first 150's came direct from Belgium and we had continual problems with them. BHG at Beaulieu sorted them out for us under warranty.
After that the 150's and 200's were pretty trouble free and offered reasonable fuel economy and oil consumption across the board. Last year we purchased 250 and 300 hpdi's and the first 250 went bang after 7 hours needing a new powerhead. Replaced and no explanation from Yamaha or dealers as to why. "They still don't know". Then, 25 hours later, "BANG". another powerhead, same engine, ""DON'T KNOW"., but I have found out the 250's have been pouring in with holed pistons and engine powerheads being replaced continually. Went to dealer the other day, a 300 with a holed piston after 90 hours, NEW POWERHEAD" BANG yes, it's gone again.
Even though Yamaha are repairing them, they cannot explain why it is happening. Bit of a time bomb really waiting for the next one. I always thought Yamaha offered the finest marine engineering but I personally think they got it wrong with the HPDI's.
Barrus motors dont have the same build quality but I think they have far more grunt at the bottom end and are more reliable than the 250/300 hpdi's.
Hope this helps

I'm about to change my current RIB with a SCORPION (the day to become a shipowner has come!!) 3 year old with a 250 Evinrud FICHT on it. The Yamaha chaps said to me that the FIHTS were full of problems heads blowing and the like and that I need to change it with something different because they FICHTS are like a time bomb (you never know when will go wrong). They recommended a Yam 300 HPDI cause is only Euro 2,000 more expenssive than the 250 HPDI. They said that the 300 is a bit sluggish (not a lot of torque in low revs) compared with the 250 and produces a lot of power at high revs. Now you say that these engines are not good either!
As this is a big investment (Euro 17,700 for the 300) I also spoke to the chaps in Evinrude who use to maintain the engine this particular boat has. The engine has done 500 hrs and has no problem what so ever and all the services have been kept by the current and previous owner (the boat is only 3 years old).
The current owner (I've learned) has upgraded the computer on the FICHT. In my books 500 hrs is a lot for an engine so I will change it one way or the other.
So what do I do? The Yamaha people and also some of the Evinrude people say that the FICHTs are not that great, you say that the HPDIs are not good either. So what go for a 300 Merc?
The coice of a 4 stroke is a bif NO as I realy do not want to get a 4 stroke since they do not have a serious track record yet.
GREAT! PROBLEMS PROBLEMS PROBLEMS

Quote: The coice of a 4 stroke is a bif NO as I realy do not want to get a 4 stroke since they do not have a serious track record yet.

Manos,

Have you considered the Honda 225 four stroke?

It may be more expensive that the Yam 300 but here in the UK you get a 5 year warranty. I would recommend you check that your Honda dealer (if you have one locally!) is cleared to work on this engine, as some in the UK are not & can't work on them without messing up the warranty.

Hi Manos
When the Ficht was introduced I know for a fact they had endless problems with the private and commercial users. Many many problems!
Then when Bombardier took over(They binned it all) and started over again with their suberb aircraft technology they developed a really good engine.
All manufacturers encounter various problems of some kind and this is envitable whether the user is "Light or Commmercial")
I am not aware of any recent problems with the new technolgy fichts, but as stated in my previous post, I am worried as to what I may encounter next with the 250/300 hpdi's.
As a charter company,and aside of what leisure users might think, we look after and service our motors on a regular basis and during a season probably use the motors between 95/140 hours.
I feel the lack of support from Yamaha is very very poor indeed. Our local dealer BHG Marine at Beaulieu, Hampshire have been very supportive and have only acted on instruction from the "Top Dogs".
Having been in the Rib Charter business for 7 years now it all seems a very hard learning curve. You buy your product in good faith and expect full support from the supplier. That we have had but not from Yamaha themselves.
1. Why did the motors go BANG!
2. What have you done to rectify the problem!
3. Might it happen again ?

Dealer ! We don't know. This is 10 months down the line.

What did Yamaha say in Japan. Nothing!! They don't know what the problem is.
PATHETIC!!

When the motors are running they appear fine. The 250/300 motors are VERY VERY thirsty and the oil consumption is unreal compared to the 150/200 range. I have been told that flat out the oil intake increases from 100 to 1 to 25 to 1 at top speed.
We run 10.5 metre Cobra Ribs and 40 miles running at full throttle will use over 1 gallon of oil.
Three quarter to full throttle for 50 miles running burns 125 litres of fuel??
I think this is massive consumption for so called new technolgy fuel efficient motors ??
What next?
Should we try the HONDA 225p V TECH. (MAY BE)

With all the marine motor companies introducing new products each year. The range is quite large. But they might be the latest development but they are not tried and tested in the leisure and commercial market.

Thanks Brambles but I really don't trust 4-strokes as yet. I believe marinised or not you cannot leave a car engine in the sea for 3-4 months (we do not take the boats in and out in Greece but we leave them on moorings for long periods) and expect it to work 100%.

Price is not that important although is a factor worth considering. I only look at reliability and I would consider anything 2-strokes but not a 4-strokes (as yet - after 10 years from now a 4-strokes engine may be will be an option for me, consumption and all that is not worth even mentioning as you save not much if any at all any way). Also I think Honda is quite a heavy engine but I may be wrong

Thanks Brambles but I really don't trust 4-strokes as yet. I believe marinised or not you cannot leave a car engine in the sea for 3-4 months (we do not take the boats in and out in Greece but we leave them on moorings for long periods) and expect it to work 100%.

Manos, you could be right. There have been problems with this engine when the boat is left in the water. That is the trouble with marinised car engines.